Military human resources (HR) systems must generate and sustain the human capability that underpins fighting power. Training pipelines, pathways comprising sequences of courses and activities undertaken by personnel to develop necessary skills, are essential components of military HR systems. However, Western military organisations including the UK Armed Forces have experienced persistent shortages of personnel in some skilled cadres leading to severe human capability challenges. Various initiatives have aimed to rectify skills shortages but these have usually taken little account of the dynamics of military training pipelines. Moreover, the literature includes few studies of military training pipelines and defence policy provides only very broad guidance on training pipeline management without precisely defining important terminology. Neither the presence nor the effects of bottlenecks in training pipelines are explicitly acknowledged in the literature or in current defence training policy.

Harrington et al. (2017) assert that supply chain management literature could be applied to training pipeline management to improve the flow of personnel through training systems. Accordingly, this paper synthesises Theory of Constraints, a mature systems-based management philosophy that has profoundly influenced modern supply chain management, with the human capability and military training pipeline literature. Drawing upon publicly available sources including government reports the paper examines how training pipelines contribute to the provision of human capability as important sub-systems within broader military HR systems and characterises the nature and effects of bottlenecks that occur within military training pipelines. From this, the paper develops principles to inform and guide the development of defence policy for training pipeline management and presents recommendations on identifying and managing bottlenecks to regulate the flow of personnel through training and improve the provision of human capability.